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An anonymous reader writes "The Seoul Metropolitan Government just rolled out the world's first commercial all-electric bus service. The buses were designed to be as efficient as possible — each bus can run up to about 52 miles on a single charge and they have a maximum speed of about 62 miles per hour. The vehicles' lithium-ion battery packs can be fully charged in less than 30 minutes and they also feature regenerative braking systems that reuse energy from brakes when running downhill."

Its hilly and congested. Many major roads are pretty much gridlocked. Urban speeds are quite slow. Many roads are steep. Motors which don't use energy when stopped are a great idea. Regenerative braking is also worth while.

Admittedly Toronto's electric buses weren't battery operated - they were powered by overhead wires - but they were in service from 1947 to 1993. That start date beats South Korea by more than 6 decades.

Cleveland has CNG buses which probably pollute less than an electric bus would given how much of our power comes from coal. They are used on almost all routes except those that go into the farthest suburbs due to the lack of filling stations.

As fun as it is to say that, not only does Chattanooga have electricity, Chattanooga also has the fastest residential internet service in the country (I think). 1gbit fiber to your home for $350/mo [epbfi.com].

My thought too. A lot of places have (and many more had) electric "buses"
except they were on tracks with overhead wires. Having
a trolley with rubber wheels, and a battery for short-gaps where you haven't
built out the overhead wires (or don't want them for aesthetic reasons) makes
sense. I heard about a bus like that somewhere in Europe that used flywheel
energy storage to traverse a roughly 2km gap between overhead wires. Sorry
I don't recall the details on that; but IIRC it was being done more than

You don't have to install cable every time you want to want to add a new a bus route. This means the routes can change more frequently, or a destination which might not merit a regular route (sports stadium, e.g.) can get bus service only when needed.

No cables means no cable maintenance and no cable theft (theft may not be a problem in Korea, but can be a big problem in some countries).

Cables have their advantages, and a city with cables in place would probably do better to keep them. I would think most places would be better off starting an electric bus system from scratch without cables.

Frequent changes to routes is a bug, not a feature, where I come from. Makes the whole damn system unpredictable if you're trying to get somewhere you don't go on a regular basis, because the route you took the last time won't get you there anymore.

Seattle has had trolleybuses for as long as I can remember. Until Metro started replacing them with hybrids they were the only ones that were allowed to operate in our transit tunnel. That included hybrids where they were able to completely switch between gas and electric, but as far as I can tell couldn't operate like the newer ones. They work well, however they aren't without their disadvantages.

For one thing they can't make 90 degree turns. Any time the driver needs to make a 90 degree turn he has to

" Any time the driver needs to make a 90 degree turn he has to get out of the bus and manually switch lines. Any time the driver needs to make a 90 degree turn he has to get out of the bus and manually switch lines."

it should be trivial to equip the trolley poles with servo motors and optical sensors so they drop as the bus pulls away from the wires and raise again when they are under another set of wires. With accurate enough sensors and actuators this could be done at cruise speed

Ever been to San Francisco? The overhead wires are the second ugliest thing in the city. Plus, there are places on the routes where drivers have to get out and adjust the wires as they're switching to a different pair. Batteries aren't a panacea, but neither are overhead wires.

Thats just bad design or outdated equipment (newsflash - trolleybuses last 50 years as unlike a diesel bus they dont shake themselves to pieces). It would be technically trivial to have the trolleypoles auto align themselves and even switch wires while moving.

The problem is trains have a very high capital cost, electric buses with overhead wires is much cheaper and adaptable, add batteries for gap coverage and you can achieve 90+% of the benefits with dedicated or HOV lanes at a fraction of the cost. Now for a city with fixed or slow moving demographics rail probably makes sense, but for most US cities with population centers that move every generation rail doesn't make much economic sense.

The title should read "battery powered buses" instead, but thet's not a great advantage for a bus. A vehicle that always runs through the same route is very easily powered by cables strung along the road.

The title should read "battery powered buses" instead, but thet's not a great advantage for a bus. A vehicle that always runs through the same route is very easily powered by cables strung along the road.

We have many of those here in Seattle, and those overhead lines are _BEYOND UGLY_.

we have the dedicated trolly bus fleet, that can switch to running on batteries when there is no power, then back to overhead lines when power is restored,

from what I can see this achieves all the positives of the Korean system and none of the negatives (return times, charge times etc) as they are full time electric but only require the battery power as a backup.

(ok the lines might be a bit unsightly to some, but my point remains)

so this might be the first electric bus system that requires no on the go charging, but is that necessarily a good thing? they still have to plug in sometime.

it is more about making a real world test of the current capabilities of what south korean companies can do so they can offer the buses to other customers. Doing this they amortize the R&D and will be able to sell at a better price than competitors. Overhead wire is dirt cheap and low maintenance; hell, even in my city here in Mexico we had several mayor routes of trolley buses, two of them were replaced by 2 lines of light rail in the 80's and early 90's, two lines are still in service an the 3-6 other

from what I can see this achieves all the positives of the Korean system and none of the negatives (return times, charge times etc) as they are full time electric but only require the battery power as a backup.

They do have some negative of their own however - like maintenance of the lines and supporting infrastructure. (Not to mention it's high capital cost.)

we have the dedicated trolly bus fleet, that can switch to running on batteries when there is no power, then back to overhead lines when power is restored

They did this when they were (up/down)grading manners street, with dedicated "pole-removers" waiting to detach buses from the wires before going past the inner city malls, then another group of workers on the other side of the malls.

I wonder if it'd be possible to automate that (i.e. computerised pole-retractors and re-attachers), which would allow the possibility for buses to transfer between charging/powered and unpowered regions of their bus route. That could make the trolley buses useful on more routes,

Here in Beijing has a lot of trolley bus too. But they have to slow down to 10mph when crossing cable intersection or a switch, and most of them are in the road intersection...which blocks all the traffic behind.

Plus, you can't have too many bus running on the street, because apparently they can't overtake each other! Imagine in busy road section where there are 4 lanes filled with vehicles and 1.5 lanes of traffic are buses.

I bet the S Koreans have a production line which could churn out a bus per day. These guys think large scale. They built a whole new island for Incheon airport. And its not just the airport on the island. Its got its own city and transit system.

That seems expensive and largely symbolic. On city routes surrounded by high-rise buildings the average insolation on the panel will be terrible, and there are better ways to spend the $thousands it will cost to generate a negligible amount of power for only an intermittent few hours a day. The reason the Prius and Fisker Karma have solar roof options is so the AC can keep the car cool while parked without draining the battery, but a bus is constantly on the move. You'd still have to size the buses' batte

Instead, these should be loaded with ultracaps that can go about 10 miles (or at least 2x the longest distance between 2 stops) or so AND handle the HVAC. Then at each stop, there is a charging station that quickly fills the bus. With an ultra-cap, you have the ability to charge as quickly as you want (as in seconds, not minutes).

Oh good, let's replace the expensive lithium batteries with even more expensive ultracaps, and then utilize a charging system which is pretty much going to have to have ultracaps in it too in order to deliver them power in a timely fashion so that people can steal them. This is a fantastic idea, and I can't imagine why they didn't use it.

How much money in lithium batteries are required to run 50 miles AND have HVAC vs. how much money in ultra-caps to run typically less than several miles and run HVAC? And there is NO reason to have ultra-caps at the site. Generally any place that runs a bus only 52 miles a day will have loads of stops along the way and it will certainly have loads of high wattage lines.

Probably a lot of you know this, but for the benefit of those who don't, S. Korea is currently pursuing an aggressive build-out of new nuclear reactors. According to the U.S. Energy Information Administration [doe.gov] S. Korea already gets 34% of its power from nuclear, and plans to be generating 50% from nuclear by 2022 (and will likely keep pushing that percentage up to the 60-80% range longer term).

If the electricity to charge the batteries in the buses comes from nuclear, it should be very low-carbon emissions, low air pollution energy. The South Koreans are also building nuclear at something like 1/2 the cost of equivalent nuclear plants constructed in the U.S., so it should be pretty cheap energy too.

S. Korea is even starting to get into the business of exporting nuclear power plants to other countries - they recently inked a deal with the United Arab Emirates to build four 1.4 GW plants in UAE for a total of $20Bn(USD).

My concern with this is that the solution limits you to certain routes. You could not have this operate on a rural bus route. Asking passengers to wait 30 minutes while the bus is recharged would be a bit ridiculous.

I don't understand why they didn't have an interchangeable battery pack. This would have allowed the bus to quickly swap out the exhausted pack and replace it with a new one and you could put the swapping stations at strategic points around the city/rural area.

This doesn't make any sense. It is a fleet of buses designed for a city. It would be a bit dumb to buy buses that cannot manage their basic routes. If you want to have a bus every 15 mins, then you just assign 2 buses per route. They can recharge at each terminus. An interchangeable battery pack is pointless.

With a large percentage of the worlds population, and where the pollution is largely concentrated causing large scale medical problems, in the cities it's not "one to watch" but a perfectly valid soluti

Implementing this via the bus system, to prove the tech, then rolling into other building projects.
Step 1. Induction Road beds
Step 2. City bus systems runs on electro buses
Step 3. modify Hybrid cars to run on induction
Step 4. Interstate highways are rebuilt to with the technology - reducing oil reliance, and pollution. Smug may become a problem tho.

In another slashdot discussion about a year ago, someone linked to a company called Doty Energy. They claim to have a process which can efficiently take electricity, and generate gasoline and diesel from water and waste CO2 (I think the idea is sort-of like reverse-combustion - when hydrocarbon fuels burn cleanly, the products of combustion are energy, water, CO and CO2, so theoretically, it should be possible to 'reverse' the reaction with input energy, water, and CO2 and produce synthetic gas/diesel).

I have this brilliant idea to solve the battery range problem.Since buses travel on fixed routes, you could run overhead electric wires to power them, removing the need for expensive and heavy batteries, and increasing speed.I cannot believe nobody has thought of this before [wikipedia.org], and this is the worlds first electric bus fleet.

Are the cables for transferring mechanical force? That's not particularly efficient, and you have to worry about cable stretching, ongoing maintenance, etc. But they still might have some use if you have short inclined runs at low speeds, because you can use the weight of descending cars to balance the weight of the ascending cars, and only have to actually provide power for the difference in weight and mechanical losses, which at low speeds..

My joke was: If you insist on promoting an old system (overhead cables) why not just go back all the way to cable cars?.

I assume they are only used in SF for historical reasons. We used to have them in Melbourne but replaced them with electric trams and overhead cables.

In the last decade or so a lot of devices such as street lights have been installed to run on photovoltaic and battery power. The reason is that a PV power supply is a hell of a lot cheaper than anything which involves digging trenches and ru

You say that, but the service life of a battery is probably a lot less than the service life of a power line for a sliding contact... as well as the replacement cost being higher and the technology level being higher, which causes other issues...

The city of Nice, in France, did the sums recently and still dug up the roads and built a tramway with overhead cables. This is a city that has run all its vehicles (buses, cars) on natural gas for decades, and from next year will make available a fleet of electric cars that the public can pick up and drop off as they want on street corners. They are already massive PV fans, with lots of buildings such as schools and government buildings having massive PV installations.

The city of Nice, in France, did the sums recently and still dug up the roads and built a tramway with overhead cables.

There was no choice: Batteries are still not powerful enough, plus you can't expect the trams to spend dozens of minutes at the termini while the batteries charge (BTW, Nice's trams have got propulsion batteries, but they only serve on two limited stretches where the OHLE is absent for dubious æsthetic reasons). There was talk of using a sophisticated third rail system for line 2, but I think this was one more of Mr. Estrosi's regular wild proclamations without actual consequences.

This is a city that has run all its vehicles (buses, cars) on natural gas for decades

I remember reading about a bus system a couple of years ago, in Switzerland as I recall, that used induction charging at the stops. This is cheaper (and less ugly) than laying overhead wires everywhere, and it means that the battery only has to last the distance between two stops. When the bus stops, it automatically starts charging and the charging times are factored into the time table.

Spanning electrical lines everywhere has drawbacks too. They require constant maintenance, they hinder traffic, may interfere with power lines/tram lines or other obstructions and on top of that, they come down once in a while. They are butt-ugly too, try to make a decent picture in a city using lots of trams or trolleys - near impossible at times.

Besides that, imagine building this grid only to find out that everybody is switching to the latest battery tech, that's a high initial investment you might be th

For one, they are a nuisance on the road - they really do interrupt the flow of traffic and often get in the way.

How exactly is this specific to trolleybuses? I can think of lots of vehicles interrupting the flow of traffic: Delivery vans parked anarchically, for instance.

Another one is the fact that if one breaks down, it can either a) completely block the flow for other trolley buses or hopefully b) create a large obstacle which other trolley buses have to somehow pass very slowly because their "antlers" have a limited reach, which of course means 2 lanes of road that get clogged.

It looks like Moscow's mayor is a cheapskate who didn't pay a little more to buy trolleybuses equipped with onboard batteries/diesel generators like every modern system has done since the eighties. Well, tough. Anyway, without that oversight, this is a non-issue

With this year's winter, loads of them stalled as well because the lines frosted over, etc.

Again, having no backup system is dumb, plus not performing a defrosting run in the mornin

Sure there are many other vehicles that interrupt the flow of traffic - so the more the merrier? I don't see your point at all, one less is still better.

My point is that I don't see yours either: You didn't point to a trolleybus-specific property that makes them more prone to interrupt the flow of traffic (I can see why a frequently-stopping transport vehicle can impede traffic flow, of course, but a bus, tram or truck would have the same issues).

However, playing devil's advocate here, but batteries or a diesel generator drive up cost significantly whereas the OP was promoting trolleybuses because they are cheaper.

Depends. A few batteries to pass works areas or obstacles in the way do not add that much (Rome has such a system to avoid running the overhead wires in the historic city center). Anyway, the added flexibility and

As the poster said below, 52 miles is along way for an inner city bus. Also, the article discusses regenerative breaking and it seems as though the 52 min is pure battery without the benefits of the breaking - which can only be estimated.

Regenerative braking, by virtue of not being a method of implementing perpetual motion, is limited to generating less energy than is required to get the bus back up to the speed it was going before braking. So it won't extend the range at all, just avoid reducing the range too much in stop-start traffic.

Regenerative braking, by virtue of not being a method of implementing perpetual motion, is limited to generating less energy than is required to get the bus back up to the speed it was going before braking. So it won't extend the range at all, just avoid reducing the range too much in stop-start traffic.

I am having some difficulty being convinced that this is much better than taking the good old good trolleybus of the kind which Moscow has been running for nearly 100 years now and adding a 2 mile mini-battery to it.

It would have made much more sense to add some modern "lock/unlock to the cables" tech to a trolleybus system and use the batteries only for the intervals where there is no overhead wires so you can have interrupted coverage. This way you also do

You do realize that a bus is a mass transport vehicle that stops every few blocks to pick up passengers and typically doesn't go more than about 40mph on most routes, right? Sure there are buses that travel further and faster, but that's not the norm, most buses are for use in cities at normal speeds.

What kind of buses do you take? Is there a freeway circling around downtown, where a single bus cruises at a constant 62 miles per hour? And passengers are catapulted from the city into the bus and vice versa?

Wellington's trolleybuses have been there since 1949, and they were by no means the first. Pyongyang has also had electric buses since 1964. You'd think they'd check these things before making a song and dance about it and handing a propaganda opportunity to their neighbours on a platter.